Rate of nicotine metabolism on risk of myocardial infarction among people with HIV who smoke cigarettes

Background The prevalence of cigarette use in people with HIV (PWH) is 2–3 times higher than the general population. Cigarette use increases risk of myocardial infarction (MI). Faster nicotine metabolism, quantified by the nicotine metabolite ratio (NMR) is associated with greater risk for nicotine dependence and lung cancer, but its association with MI is unknown. Methods We conducted a nested case-control study within the Center for AIDS Research Network of Integrated Clinical Systems (CNICS) cohort. Cases were PWH who reported cigarette use with incident adjudicated MI between 2003 and 2020 and available plasma samples; cigarette-smoking controls were selected by incidence density sampling, matched on age, race, birth sex, and plasma HIV RNA level. Conditional logistic regression was used to estimate odds ratios (OR) for the association of NMR and MI. Results We identified 135 cases with MI and 252 controls. Median (IQR) NMR was greater in cases [0.51 (0.36, 0.73)] than in controls [0.47 (0.30, 0.70)]. In conditional logistic regression, the odds of having a high NMR were 1.4 times greater among MI cases than controls, but not at a statistically significant level (OR: 1.4, 95% CI: 0.97–1.9). This estimate did not substantively change after further adjustment for statin use, hypertension, and diabetes (OR: 1.4, 95% CI: 0.92–2.0). Conclusions There is a small-magnitude association between NMR and MI, which was not statistically significant. NMR remains a potential biomarker for MI risk among PWH. Further investigation is needed to estimate the precise effect of NMR on MI in PWH.